The present invention relates generally to medical devices and methods for securing body tissues and more particularly to a method and device for securing soft tissue to bone.
It is commonplace in arthroscopic procedures to employ suture anchors and tacks to secure soft tissues to bone. Despite their widespread use, several drawbacks have been noted with these techniques. Suture anchors, for example, are often undesirable as they require the surgeon to tie a plurality of knots to secure the soft tissue to the bone. The procedure of tying knots can be very time consuming, thereby increasing the cost of the procedure and limiting the capacity of the surgeon. Furthermore, the strength of the repair is limited by the strength of the knot. This latter drawback is of particular significance if the knot is tied improperly as the strength of the knot in such situations can be significantly lower than the tensile strength of the suture material.
Barbed or expanding tacks are often times not desirable due to the difficulty of their removal should the surgeon decide that they have not been positioned correctly after their insertion into the bone. Furthermore, it is generally not possible to xe2x80x9cfine-tunexe2x80x9d the degree of compression that the tack exerts onto the soft tissue. If the tack is implanted too deeply and compresses the soft tissue to a higher degree than that which is desired, it is not possible to back the tack out of the hole in the bone to relieve the pressure exerted onto the soft tissue.
Many of the known tacks are formed with a round head or are used in conjunction with a washer. In some situations, such as the attachment of soft tissue to the glenoid rim, tacks having these configurations can protrude past the bone and impinge upon other bones in the joint (e.g., the humeral head) when the bones in the joint are moved relative to one another.
In one preferred form, the present invention provides a fixation device for engaging the soft tissue in a body. The fixation device includes a body portion and a plurality of teeth. The body portion has a proximal face, a distal face, a central aperture and a suture slot. The central aperture is formed through the proximal and distal faces and is configured to receive a screw. The suture slot intersects the central aperture and is configured to receive a suture. The plurality of teeth coupled to the proximal face of the body portion and are configured to engage the soft tissue.
In another preferred form, the present invention provides a tissue securing device for securing soft tissue to a bone. The soft tissue securing device includes a suture, a fixation device and a screw. The suture has a looped section and a pair of ends. The fixation device has a body portion, a plurality of teeth and a suture guide. The body portion includes a proximal face, a distal face, a central aperture and a suture slot. The central aperture is formed through the proximal and distal faces and configured to receive the screw. The suture slot intersects the central aperture and receives the looped section of the suture. The plurality of teeth are coupled to the proximal face of the body portion and are configured to engage the soft tissue. The suture guide is coupled to the proximal face of the body portion and extends between the ends of the suture slot. The screw is disposed through the central aperture and abuts the suture guide. The suture guide guides the suture around a side of the screw in response to the application of tension to the ends of the suture.
In another preferred form, the present invention provides a method for securing soft tissue to a bone. The method includes the steps of: providing a drill having a guide aperture formed therethrough along a longitudinal axis of the drill; providing a guide member having a driver portion, the driver portion having a non-circular cross section; inserting the guide member into the guide aperture; forming a hole in the bone with the drill; translating the guide member into the hole; removing the drill from the hole while maintaining the guide member in the hole; providing a soft tissue securing device having a fixation device and a screw, the fixation device having a body portion with a proximal face and a central aperture, the screw having a threaded portion and a hollow cavity configured to mate with the driver portion, the hollow cavity being formed through the screw and having a portion with a non-circular cross section, the screw being disposed through the central aperture; aligning the hollow cavity to the guide member; translating the screw along the guide member and into contact with the bone; and rotating the guide member so that driver portion rotates the screw thereby causing the threaded portion of the screw to threadably engage the bone and exert a clamping force onto the fixation device to secure the soft tissue to the bone.